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They are instantly recognisable thanks to their distinctive wings, long bodies and bulbous eyes.

Now scientists have discovered that dragonflies have the best vision in the animal kingdom.

While humans can see colours as a combination of red, blue and green, the insect has up to 33 different types of light sensitive proteins, meaning that it can see more colours and details.

Scientists have discovered that dragonflies have the best vision in the animal kingdom, perhaps explaining why they are such effective predators. They have found that dragonflies have between 15 and 33 opsin genes – 'an extraordinary large number,' which enable them to see in incredible detail

Researchers from the Tokyo University of Agriculture, Sokendai, Kitasato University and the National Institute of Advanced Industrial Science and Technology (AIST) in Tsukuba, Japan, studied the compound eyes of 12 species of the creatures.

They found that dragonflies have between 15 and 33 opsin genes – 'an extraordinary large number,' which enable them to see in incredible detail.

Opsins are light sensitive proteins found in the retinas of humans and animals.

By comparison, humans have tri-chromatic vision, meaning we seen in red, blue and green thanks to three opsins. 

While it is impossible for scientists to see the world through a dragonfly's eyes, the researchers think they are probably able to see more colours than humans. Previous studies have found that dragonflies can see ultraviolet on top of blue, green and red, which aids them in hunting prey. A Black-tailed skimmer is shown

Each type of opsin absorbs one colour of light in the spectrum and the different wavelengths of light reflected from objects mix together, enabling us to see some 10 million different colours.

Tri-chromatic vision is common among mammals, birds, and other animals, including insects, the study, published in the journal PNAS, says.

It also reveals that dragonflies use different opsins at different times in their lives.

For example, the larvae of some species that hatch in sand tend to lack blue opsins, because blue light does not reach them easily, New Scientist reported. 

While it is impossible for scientists to see the world through a dragonfly's eyes, the researchers think the insects are probably able to see more colours than humans.

Previous studies have found that each of a dragonfly's bulbous eyes are made up of up to 30,000 facets, which contain the opsins.

Each facet points in a slightly different direction, enabling dragonflies to see in all directions at the same time. 

The visual sensing elements together produce a mosaic of 'images' which are integrated in the creature's brain. Although, how this happens is a mystery.

Dragonflies can see ultraviolet on top of blue, green and red, which aids them in hunting prey.

The position of opsins in their eyes indicates they may see the sky brighter than humans, so that flying prey appears clearer, Dennis Paulson, a dragonfly expert at the Slater Museum of Natural History at the University of Puget Sound, in Tacoma, told Science Blogs. 

...DRAGONFLIES ARE THE WORLD'S DEADLIEST HUNTERS TOO 

In December, Scientists at the Howard Hughes Medical Institute in Virginia, claimed that dragonflies are nature's most successful predator when it comes to catching prey.

The winged insect catches more than 95 per cent of the prey it targets - making it twice as successful as a great white shark, and four times as effective as a lion.

Dragonflies eat mosquitoes and other small insects such as flies, bees, ants and wasps, as well as the occasional butterfly, which they hunt around marshes, lakes, ponds, streams and wetlands.

The reason the dragonfly is such as effective hunter is that when targeting its prey, the insect keeps it in sight while adjusting its flight, and can predict how it will move before catching it.

Dragonflies (pictured) catch more than 95 per cent of the prey they target - making them twice as successful as a great white shark, and four times as effective as a lion

The researchers likened the insect's calculations - about its own movements and those of its target - to those used by a ballet dancer to catch his partner. It's the first example of such skill in invertebrates.

Its huge eyes provide an almost spherical view of the world while the insect perches on a leaf waiting for prey to fly overhead.

When the time is right, it shoots off in pursuit, scooping up victims with its hairy legs in a fraction of a second.

Its visual sharpness and lightning-quick reflexes - thanks to specialised neurons that detect the motion of a target and instruct its wings to react - make it a formidable hunter.

High-speed measurements show how the dragonfly tracks the position of a fly and steers itself quickly towards it, relying on both prediction and reaction.

Scientists fitted insects with tiny reflective markers and used motion-capture technology to record the insects in action at 1,000 frames-per-second, replaying the film 20 times slower to analyse tiny movements.

The footage demonstrated that dragonfly manoeuvres are generated by predictions of prey movement combined with visual reactions.

This allows the insect to estimate the position of a fly, for example, and determine the wing and head movements required to catch it.

To avoid detection, a dragonfly approaches from below and aligns its body to the prey's direction of motion.

Its body and head move independently, with the latter locking on to the target while its body manoeuvres to the best position for capture.

The study, published in Nature, indicates steering behaviour in dragonflies is more sophisticated than previously thought - but whether this is the case for other invertebrates remains to be seen.